Devices or unwinders of this type, respectively, are employed in the manufacturing of web-shaped materials, for example. The material web is thereafter wound on a production line by a winder onto a winding core so as to form a master roll. The master roll here has comparatively large dimensions, for example a diameter of 2 m and more, and a web width of more than 2 m.
The completely wound master rolls are first temporarily stored in a transfer region which thus serves as a buffer. Subsequently, the master roll is unwound off line with the aid of an unwinder and cut to measure according to customers' specifications in a downstream cutting line, for example.
On account of the cutting line having the device for automatic unwinding, that is to say having the unwinder, operating in an offline manner, the production line during a temporally limited period may run at a higher production rate than the cutting line. Downtime is created by the required changeover of the master rolls in the unwinder. Here, after the winding core of the unwound master roll has been removed, an end of the material web of the new master roll has to be guided over by way of the unwinder to the downstream cutting line. This requires the intervention of at least one operator, bears a certain susceptibility to errors, and leads to downtime. Since the master roll has to be replaced every couple of hours, the efficiency of the entire line is negatively influenced by these occurrences of downtime.